Mixing valve

ABSTRACT

A mixing valve which provides water of a constant temperature when connected to sources of hot and cold water. The valve comprises a cylindrical housing having first and second axially aligned spaced inlet connectors, a rotatable pressure selection element positioned within the housing, an axially translatable presure equalizing element positioned within the pressure selection element and a rotatable temperature selection element positioned within the pressure equalizing element. The pressure selection element has first and second ports substantially aligned with the inlet connectors to the housing, the pressure equalizing element has first and second ports axially aligned and angularly displaced from the first and second ports in the pressure selector and the temperature selection element has first and second ports angularly displaced with respect to each other and to the first and second ports in the pressure equalizing element. Rotation of the pressure selection element adjusts the volume of water discharged per unit time from the valve and rotation of the temperature selection element adjusts the ratio of hot to cold water discharged.

BACKGROUND OF THE INVENTION

This invention relates to mixing valves and, in particular, to mixingvalves for use with faucets.

Mixing valves are frequently used with kitchen and bathroom faucets toobtain water at a desired temperature and rate of flow from separatesources of hot and cold water. Rather than providing one valve forcontrol of the volume of hot water delivered to a discharge outlet in agiven period of time and a second valve for control of the flow of coldwater to the outlet, a single mixing valve combines the hot and coldwater to control both the temperature and the flow rate of the water atthe discharge outlet. This may be accomplished by providing a firstadjustment for controlling the ratio of the volume of hot to the volumeof cold water delivered to the outlet per unit time, and a secondadjustment for controlling the total volume of water released from theoutlet during a given amount of time.

In the past, mixing valves have employed relatively complicated valveoperating mechanism requiring the assembly of many parts. Although someprior art devices have separate handles for controlling volume of flowand temperature, others employ a single handle which controls both watertemperature and volume. However, with a single handle device, thetemperature of the water is often changed accidentally when adjustingthe flow rate.

Summarizing, prior art mixing valve operating mechanisms often utilize alarge number of assembled parts, and are relatively difficult todisassemble and repair. Further, with some of the devices commonly inuse, it is easy to accidentally change the temperature setting when thevolume of water is changed and, therefore, with each new use of thevalve, the temperature must be readjusted. Thus, there is a need for amixing valve of simple construction in which the temperature of thewater does not change as the rate of flow is varied.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an improved fluidmixing valve which can be used to provide water of a desired temperatureand rate of flow at the discharge outlet of a faucet.

It is another object of the invention to provide a mixing valve having asimple valve operating mechanism utilizing a minimum number of parts.

Still another object is to provide a mixing valve which can be easilydisassembled for repair.

It is a further object of the invention to provide a mixing valve with afluid ratio control that will permit the temperature of the water toremain constant as the flow rate is adjusted.

In accordance with the present invention, a mixing valve is providedwhich comprises a cylindrical housing having first and second axiallyaligned spaced inlet connectors coupled to first and second sources offluid. Fluid blocking devices are located within each of the inletconnectors to prevent fluid from entering the valve when the valve isclosed and permit the flow of fluid when a rotatable flow rate orpressure selection element is turned from its off position. The pressureselection element has first and second axially spaced ports which aresubstantially aligned with the first and second inlet connectors in thehousing.

An axially translatable pressure equalizing element positioned withinthe coaxial with the pressure selection element has first and secondaxially spaced ports which are angularly displaced, preferably at 180°,with respect to the first and second ports of the pressure selectionelement. An external flange forming part of the pressure equalizingelement is interposed between its first and second ports.

A rotatable cylindrical temperature selection element is positionedwithin and coaxial with the pressure equalizing element. The temperatureselection element has first and second axially spaced ports which areangularly displaced with respect to the first and second ports in thepressure equalizing element. With this configuration, the ratio of thefluids from the first and second sources is controlled by the angulardisplacement of the temperature selection element with respect to theports in the pressure equalizing element. Water at a desired temperatureand rate of flow is delivered from an end of the temperature selectionelement.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external view of the mixing valve of the present invention.

FIG. 2 is a cross-sectional view of the valve.

FIG. 3 is a section of the valve taken along the lines 3--3 in FIG. 2.

FIG. 4 is a cross sectional view of the valve taken along the lines 4--4in FIG. 2.

FIG. 5 is a perspective cutaway view of the mixing valve.

FIG. 6 is an exploded view showing the components comprising the valve.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, there is shown the mixing valve 8 of this inventionwhich comprises a cylindrically shaped housing 10 coupled through aninlet connector 12a to a pipe 14a which carries hot water to the valve.An inlet connector 12b couples the housing 10 to a pipe 14b whichsupplies cold water to the valve.

Located within the housing 10 is a cylindrically-shaped rotatablepressure selection element 20. The pressure selector 20 is rotatedwithin the housing by turning handle 22 affixed to its upper end.Rotation is limited by a stop 24 on the pressure selector and a stop 26on the housing.

A cylindrically-shaped temperature selection element 28 is coaxiallymounted within the pressure selector 22. The temperature selector 28 isrotatable by turning handle 30, the angle of rotation being limited by astop 32 on the temperature selector and a stop 34 on the pressureselector. Water is discharged through a discharge outlet 36 at the lowerend of the temperature selector 28. A spout 38, as shown in FIG. 6, maybe threaded onto the nozzle discharge outlet. An internally threaded cap40, provided with a centrally located opening 42 (FIG. 2), is attachedto external threads on the upper end of the temperature selector 28, asshown in FIGS. 2 and 6.

Referring to FIGS. 2 and 6 which show cross-section and exploded viewsrespectively of the components of valve 8, fluid blocking assembliesconsisting of ring seals 44a and 44b, spherical elements 46a and 46b andfilter elements 48a and 48b are located within hot and cold water inletconnectors 12a and 12b respectively. The spherical elements 46a and 46bare driven by the pressure of the water in pipes 14a and 14b againstring seals 44a and 44b respectively thereby preventing water fromentering the valve 8. Filters 48a and 48b, which are seated on flangesformed on the insides of the connectors 12a and 12b, prevent foreignmatter from entering the valve.

The pressure selector 20 is provided with two spaced axially alignedports 50a and 50b which are located opposite the openings in inletconnectors 12a and 12b respectively. Slidably positioned between thepressure selector 20 and the temperature selector 28 is a pressureequalization element 52 which is also cylindrically shaped. The pressureequalizer 52 is provided with two axially spaced, aligned ports 54a and54b which are offset with respect to the openings in connectors 12a and12b, respectively, by an angle of 180°. Ports 54a and 54b are separatedby a pressure chamber separation ring or flange 56.

Temperature selector 28 is provided with two axially spaced ports 58aand 58b. As shown in FIGS. 3 and 4, port 58a is angularly displacedcounterclockwise from port 54a in pressure equalizer 52 by 45° and port58b is angularly displaced clockwise by 45° from port 54b in thepressure equalizer.

Flange 56 is provided with two opposing notches 60 which are alignedwith two guide ribs 62 running lengthwise on the inside wall of thepressure selector 20. Notches 60 and guide ribs 62 allow pressureequalizer 52 to translate along the axis of the valve 8 but do notpermit it to rotate. An upper annular chamber 64a is formed in the spacebetween the portion of pressure equalizer 52 above flange 56 and thepressure selector 20, and a lower annular chamber 64b is formed in thespace between the portion of the pressure equalizer before the flangeand the pressure selector.

Ports 50a and 50b of the pressure selector 20 are axially bisected bypins 66a and 66b, respectively. The pressure selector 20 fits tightlyinto the outer housing 10, three axially spaced o-rings 68 beinginterposed between the pressure selector and the housing to preventleakage from the valve and provide bearing surfaces. Two axially spacedo-rings 70 are similarly interposed between the temperature selector 28and the pressure equalizer 52.

In operation, hot water from pipe 14a and cold water from pipe 14b enterthe valve 8 through inlet connectors 12a and 12b. When ports 50a and 50bof pressure selector 20 are aligned with inlet connectors 12a and 12b,the pressure of the water in pipes 14a and 14b forces spherical elements46a and 46b against ring seals 44a and 44b preventing water fromentering ports 50a and 50b. When the valve is "off" spherical elements46a and 46b assume the positions shown in dashed lines FIGS. 2-4. As thepressure selector 20 is rotated away from the "off" position, thespheres 46a and 46b are identically forced away from the ring seals 44aand 44b by pins 66a and 66b. When this occurs, water from pipes 14a and14b enters the valve 8 through ports 50a and 50 b of the pressureselector 20.

Water entering ports 50a and 50b of pressure selector 20 builds uppressure in annular chambers 64a and 64b between the slidable pressureequalizer 52 and the pressure selector 20. The pressure is increased inthese chambers because ports 50a, 50b of pressure selector 20 and ports54a, 50b of pressure equalizer 52 are offset respectively by 180° andthe water must travel around the pressure equalizer. When the pressuresof the water from the hot and cold water sources are equal, the pressureequalization element 52 is balanced halfway between the pressureselector ports 50a and 50b. If pressure from one source decreases withrespect to the other, the pressure equalizer slides along guide ribs 62towards the port of lower pressure. This has the effect of allowing morewater to enter the chamber of lower pressure and less water to enter thechamber of higher pressure. In this way, the ratio of hot to cold waterdelivered to the outlet tends to remain constant despite changes in thepressures of the water sources relative to each other.

As explained above, ports 54a and 54b of pressure equalizer 52 areaxially aligned and offset by 180° with respect to the axially alignedports 50a and 50b in the pressure selector 20. Ports 58a and 58b in thetemperature selector 28 are also axially spaced but are offset by 45°with respect to the ports 54a and 54b in equalizer 52. Because of thisrelationship, rotation of temperature selector element 28 by turninghandle 30 causes the alignment of ports 58a and 58b to change withrespect to that of ports 54a and 54b to admit water only through port58a (hot), only through port 58b (cold) or in any desired ratio of hotto cold water. The water flows through ports 50a and 50b of pressureselector 20, ports 54a and 54b of pressure equalizer 52, ports 58a and58b of temperature selection element 28 and out through discharge outlet36.

Thus, by adjusting handle 30, the desired water temperature is selected.Pressure equalizing element 52 keeps the water temperature relativelyconstant despite differences in the water pressures of the hot and coldsources. The volume of water flowing through the outlet in a given timeis controlled by adjusting handle 22 of the pressure selector 20.

The four elements are held together by cap 40 which is attached totemperature selector 28 by a threaded connection. By blocking water flowthrough outlet 36, water can be diverted to the aperture 42 in cap 40 toprovide a drinking fountain or an upwards rincing spray. If this featureis not desired, a solid cap can be used instead of one having anaperture.

The mixing valve of the present invention is advantageous in that therelationship between the pressure selection element and the temperatureselection element remains constant as the pressure selection element isrotated. The temperature of the water thus remains constant as the waterflow is adjusted. The temperature setting is changed by rotating thetemperature selection element handle with one hand while holding thepressure selection element handle with the other hand to keep it fromrotating. In this way, the relative positions of the two cylinders arechanged. This arrangement eliminates the possibility of inadvertentlychanging the temperature when the flow is adjusted, and is a safetyfeature which reduces the possibility of accidental scalding.

The mixing valve is far simpler in design than prior art devices, beingconstructed essentially of four cylinders held together by a cap. Thevalve can be easily disassembled by the average user to replace parts,without need for special tools or the services of a plumber.

By attaching various connections to the top and bottom outlets, it ispossible to adapt the valve for a variety of uses, such as for abath-shower combination. The mixing valve of the present invention mayalso be used for other purposes requiring the controlled mixing of twofluids.

It will be understood that the above description of the presentinvention is susceptible to various modifications, changes andadaptations, and the same are intended to be comprehended withing themeaning and range of equivalents of the appended claims.

What is claimed is:
 1. A mixing valve for mixing fluids emanating fromfirst and second sources, comprisinga cylindrical housing having firstand second axially aligned spaced inlet connectors for coupling to saidfirst and second sources respectively, each of said first and secondinlet connectors being provided with fluid blocking means for impedingthe flow of fluid therethrough; a rotatable pressure selection elementpositioned within said housing, said pressure selection element havingfirst and second axially spaced ports substantially aligned with saidfirst and second inlet members, rotation of said pressure selectionelement displacing said fluid blocking means to permit fluid from saidfirst and second sources to enter the first and second ports of saidpressure selection element; an axially translatable pressure equalizingelement positioned within said pressure selection element, said pressureequalizing element having first and second axially aligned spaced portsangularly displaced from the first and second ports of said pressureselection element, a flange being interposed between the first andsecond ports of said pressure equalizing element; a rotatabletemperature selection element positioned within said pressure equalizingelement and having first and second axially spaced ports, said first andsecond ports being angularly displaced with respect to each other and tothe first and second ports respectively in said pressure equalizingelement; and fluid discharge means coupled to said temperature selectionelement, the fluid emanating from said discharge means having a volumeper unit time determined by the angular displacement of said pressureselection element and a temperature determined by the angulardisplacement of said temperature selection element.
 2. A mixing valve asdefined by claim 1 wherein the angular displacement of the first port ofsaid temperature selection element is approximately 45° counterclockwisefrom the first port of said pressure equalizing element and the angulardisplacement of the second port of said temperature selection element isapproximately 45° clockwise from the second port of said pressureequalizing element.
 3. A mixing valve as defined by claim 1 wherein saidfluid blocking means comprise first and second spherical elements, saidspherical elements nesting withing the first and second portsrespectively of said pressure selection element when said valve is shutoff and being identically displaced from said nesting position when saidpressure selection element is rotated.
 4. A mixing valve as defined byclaim 1 wherein the ports in said pressure equalizing element areangularly displaced 180° from the angular position of the inlet membersin said outer housing.
 5. A mixing valve as defined in claim 1 whereinsaid fluid discharge means comprises a spout secured to one end of saidtemperature selection element.
 6. A mixing valve as defined in claim 5which further comprises a cap insertable in said pressure selectionelement and threadably engaged with the other end of said temperatureselection element, said cap securing said pressure selection, pressureequalizing and temperature selection elements in alignment.
 7. A mixingvalve as defined in claim 6 wherein an aperture is provided in said cap,fluid being ejected through said aperture when it is prevented frombeing released through said spout.